Synovial Biomarker Quantification in Osteoarthritis

Synovial fluid was collected from the operated knee before euthanization and centrifuged at 12,500 rpm for 10 min at 4 °C. Synovial concentrations of COMP, CTX-II, MMP-3, IL-1β, and TNF-α were measured using ELISAs in accordance with previous reports [15 (link),16 (link),49 (link),58 (link)], using methods similar to those described for the serum measurements. A rabbit COMP ELISA kit (MBS721182, MyBioSource, San Diego, CA, USA), rabbit CTX-II ELISA kit (MBS705896, MyBioSource, San Diego, CA, USA), rabbit MMP-3 ELISA kit (MBS2502146, MyBioSource, San Diego, CA, USA), rabbit IL-1β ELISA kit (LS-F23299, LSBio Seattle, WA, USA) and rabbit TNF-α ELISA kit (MBS2500169, MyBioSource, San Diego, CA, USA) were used.